Sydney, July 28: Scientists have identified a brain mechanism that derails decision-making in people suffering from schizophrenia -- a mental disorder characterised by a breakdown of thought processes and emotional responsiveness, besides attacks of hallucinations and delusions.
 The study, led by Thomas Weickert, psychiatrist at The University of New South Wales, found that a brain area called the ventral striatum, which lights up in response to rewards in healthy adults and is linked with decision making, was unresponsive among schizophrenics.
 Specifically, the study showed that they were unable to distinguish between expected and unexpected rewards or deal with life's unpredictability or make sound decisions, the journal Molecular Psychiatry reports.
 "Using functional MRI images, we could see that this region of the brain wasn't firing correctly. People with schizophrenia... have trouble taking cues from their environment and, consequently, can make some bad decisions," Weickert said.
 Reward responses are important in many areas of learning because they help us to redirect attention and behaviour towards things that are beneficial to us, Weickert said, according to a New South Wales statement.
 The ventral striatum is connected to other parts of the brain that are important in decision making, planning and cognition and is, consequently, attracting increasing interest from researchers.
 Weickert said healthy adults in the study had no trouble dealing with unpredictability, but people suffering from schizophrenia were not able to tell the difference between expected and unexpected rewards. IANS

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